<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <!--来个新的标签，style -->
    <style>
        h1{
            color: red;
            font-size: 50px;
        }
        h2{
            color: green;
            font-size: 40px;
        }
    </style>
</head>

<body>
    <h1>我是一个h1标题</h1>
    <h2>我是一个h2标题</h2>
</body>

</html>